An apparatus (1) for terminating or canceling the rotating electrical activity (2) in the heart tissue (3).Device (1) isAn electrical state sensor that detects at least one electrical parameter for a cardiac tissue；An electrical state analyzer (9) that is connected to an electrical state sensor (8) and analyzes at least one electrical parameter to the rotating electrical activity (2) in the heart tissueA pulse generator (19) that is connected to an electrical state analyzer (9) and generates an electrical pulse in response to the rotational electrical activity (2) in the heart tissueAnd an electrical pulse connected to the pulse generatorA pulse applicator (20) applied as an electric field pulse extending across the cardiac tissue.The electrical pulse includes a rotating electrical activity termination or cancellation pulse (28) and a plurality of rotating electrical activity synchronous pulses (27) preceding the rotating electrical activity termination or cancellation pulse (28).A rotating electrical activity synchronous pulse (27) is disposed at a first interval (tsync) and the rotating electrical activity termination or cancellation pulse (28) is in the range of 0.7-1.2 times of one of the first intervals (tsync) after the last one of the plurality of rotating electroactive synchronous pulses A second interval (. Delta. T) is arranged.At least one of the first electric field energy (pesync) delivered to the heart tissue (3) by each of the first maximum electric field strength (fssync) produced by each of the rotating electroactivity synchronous pulses (27) and the rotating electroactivity synchronous pulse (27) isRespectively67 or less than 82% of the second maximum electric field strength (fsort) generated by the rotating electrical activity termination or cancellation pulse (28), or 67 of the second electric pulse energy (Petou) delivered to the cardiac tissue (3) by the rotating electrical activity end or cancellation pulse % or less.Diagram心臓組織（３）中の回転電気活動（２）を
